The invention relates to a cartridge seal, including an outer ring with an annular recess, the cross section of which is axially expanded toward the exterior, and a main seal attached to the outer ring by means of vulcanization. This main seal fittingly contacts an inner ring. The latter is provided with an annular projection which at least partially radially extends over the recess in the vicinity of its orifice. A preliminary seal is provided which axially engages the recess and is attached to the annular projection by means of vulcanization. This seal contacts the recess relatively movably with a first and second sealing lip in the vicinity of two essentially radially opposing counter surfaces.
A cartridge seal of this type is known from the German Patent No. DE 30 31 870. It serves the purpose of sealing a wheel of a motor vehicle; however, it has not proven to be satisfactory to the extent desired. Particularly in cases when the outside of the seal is flooded with water, the sealing effect is less than satisfactory. Also, the cartridge seal includes four component parts which have to be manufactured individually, thus increasing the total production cost. Moreover, it poses a problem to combine these individual parts to form a complete constructional unit.